Figure 3From: Lipid accumulation, lipid oxidation, and low plasma levels of acquired antibodies against oxidized lipids associate with degeneration and rupture of the intracranial aneurysm wall Ingestion of lipids by mural cells and inflammatory cells. Adipophilin was expressed in the mural cells of intimal hyperplasia or myointima -like sIA walls (A). In degenerated sIA walls, adipophilin staining does not only stain cells but mostly extracellular debris (B). CD45 and Oil-Red-O double stainings showed presence of inflammatory cells in wall areas abundant in extracellular lipid (C-D, CD45 in brown with DAB, Oil-Red-O and hematoxylin background stain). CD45 positive cells were also found in areas without lipid accumulation (marked with * in C). Most foam cells observed were CD45 negative (marked with arrows in D) and therefore not leukocytes. Expression of 15-lipoxygenase, a known intracellular oxidant of lipids (18), was found in aneurysm wall cells (E, 15-lipoxygenase in brown with DAB and hematoxylin background stain, x40 magnification). Double stainings with CD68 (F, 15-lipoxygenase in brown with DAB and CD68 in blue with AFOS, nuclear fast red background stain) demonstrated that most cells expressing 15-lipoxygenase were not CD68+ macrophages (F), although some double positive cells were also found (data not shown).Back to article page